1. Field of the Invention
The present invention relates to a seat with an air suspension and in particular to a seat with an air suspension which is capable of automatic height adjustment depending upon the weight of an occupant of such seat.
2. Description of the Prior Art
A conventional vehicle seat is well known that is provided with an air suspension for maintaining the height of the seat at a predetermined level regardless of the weight of an occupant.
In such a conventional seat with an air suspension, the air to be charged into the air suspension is manually adjusted, or alternatively an air valve is mounted to pantographic links provided between a seat frame and a lower suspension on a vehicle floor, and when the air valve is lowered down to a predetermined position the air valve is butted against a stopping portion and a switch valve is opened to discharge air into the air suspension, so that the height of such seat can be held in the predetermined level independent of the weight of the occupant.
However, the conventional seat with an air suspension of the manual operation type is typically found poor in operability and difficult to adjust properly. On the other hand, in case of the type using the air valve to be opened or closed mechanically, the switch valve or other components are larger in size and thus installation and adjustment operations of such seat are more complicated.